Not sure if I'm the first to notice this, but the HM801 is gone from Hifiman.com and Head-direct.com. Perhaps the new player is coming sooner than we think. Hifiman is certainly taking the DX100 seriously.
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Well, the ESS chip is an excellent choice, although one of the new Burr Browns from home DACs would work nicely too. They seem to prefer not using sigma delta chips...I love my PCM1704UK based RE-7 DAC but my DX100's built in dac is terrific too. To really outcompete the DX100 they need to make it even smaller but with the same SQ, a more open OS like android, and balanced output + digital inputs. Not an easy task...